US 12020734

Here's a concise summary of US Patent 12020734:

US Patent: 12020734

• Title: Multilayer exchange spring recording media
• Assignee: Mr Technologies GmbH
• Inventors: Dieter Suess
• Filing Date: 2021-10-04
• Issue Date: 2024-06-25
• Abstract: A multilayer exchange spring recording media consists of a magnetically hard magnetic storage layer strongly exchange coupled to a softer nucleation host. The strong exchange coupling can be through a coupling layer or direct. The hard magnetic storage layer has a strong perpendicular anisotropy. The nucleation host consists of one or more ferromagnetic coupled layers. For a multilayer nucleation host the anisotropy increases from layer to layer. The anisotropy in the softest layer of the nucleation host can be two times smaller than that of the hard magnetic storage layer. The lateral exchange between the grains is small. The nucleation host decreases the coercive field significantly while keeping the energy barrier of the hard layer almost unchanged. The coercive field of the total structure depends on one over number of layers in the nucleation host. The invention proposes a recording media that overcomes the writeability problem of perpendicular recording media.

Plain-Language Overview of Independent Claims:

The patent contains one independent claim: Claim 1.

• Claim 1: This claim describes a magnetic recording system. It includes a writing head and a disk with a magnetic recording medium. The medium consists of:
  • An essentially non-magnetic substrate.
  • An underlayer.
  • An exchange-coupled magnetic multilayer structure, which itself includes:
    • A hard magnetic storage layer made of a perpendicular anisotropy material with a coercive field (Hs) greater than 0.5 Tesla. This layer is positioned with the underlayer between it and the non-magnetic substrate.
    • A nucleation host, which has a lower coercive field (Hn) than the hard magnetic storage layer (Hn < Hs) when considered without the hard magnetic storage layer. This nucleation host is formed on top of the hard magnetic storage layer (meaning the hard layer is between the nucleation host and the substrate). It is exchange coupled to the hard magnetic storage layer.
    • The nucleation host itself has at least two ferromagnetic layers: a first layer with anisotropy K1, and a second layer (closer to the hard magnetic storage layer) with an increased anisotropy K2 (K2 > K1). These first and second ferromagnetic layers within the nucleation host are connected by an exchange coupling layer.

CAFC 2026 Dockets:

A search of the CAFC 2026 dockets did not return any specific litigation cases involving patent US12020734.

Based on the provided patent text for US12020734, the following litigation is known:

1. US case in Minnesota District Court

   • Jurisdiction: Minnesota District Court
   • Case Number: 0:25-cv-01460
   • Filing Date: Not specified in the provided patent text.
   • Plaintiff(s): Not specified in the provided patent text.
   • Defendant(s): Not specified in the provided patent text.
   • Outcome/Current Status: Active litigation, classified as "Critical" by Google Patents.

2. First worldwide family litigation

   • Jurisdiction: Not specified, refers to "worldwide family litigation".
   • Case Number: Not specified in the provided patent text.
   • Filing Date: Not specified in the provided patent text.
   • Plaintiff(s): Not specified in the provided patent text.
   • Defendant(s): Not specified in the provided patent text.
   • Outcome/Current Status: Active litigation, classified as "Critical" by Google Patents.

3. US case in California Central District Court

   • Jurisdiction: California Central District Court
   • Case Number: 8:24-cv-01848
   • Filing Date: Not specified in the provided patent text.
   • Plaintiff(s): Not specified in the provided patent text.
   • Defendant(s): Not specified in the provided patent text.
   • Outcome/Current Status: Active litigation.

4. US case in California Central District Court

   • Jurisdiction: California Central District Court
   • Case Number: 8:25-cv-00786
   • Filing Date: Not specified in the provided patent text.
   • Plaintiff(s): Not specified in the provided patent text.
   • Defendant(s): Not specified in the provided patent text.
   • Outcome/Current Status: Active litigation.

5. PTAB case IPR2026-00016

   • Jurisdiction: PTAB (Patent Trial and Appeal Board)
   • Case Number: IPR2026-00016
   • Filing Date: Not specified in the provided patent text.
   • Plaintiff(s): Petitioner not specified in the provided patent text.
   • Defendant(s): Patent Owner is MR Technologies GmbH (current assignee of US12020734).
   • Outcome/Current Status: Not Instituted - Procedural.

Searches on Unified Patents, PACER, and CAFC did not yield additional specific litigation details for patent US12020734 beyond what was already listed in the patent document itself. Therefore, specific plaintiff(s), defendant(s), and precise filing dates are not available from the provided text for all listed cases.

Proceedings overview

One AIA trial proceeding has been filed against US patent 12020734. This proceeding resulted in a discretionary denial of institution. All claims of US12020734 remain untested by a Final Written Decision and are therefore sustained. This provides a patent owner with a relatively strong defensive posture, as the patent has not been subjected to a full merits review at the PTAB.

IPR2026-00016 — Resonac Hard Disk Corporation et al. v. Dieter Suess

• Type: Inter Partes Review
• Filed: 2025-10-08
• Status: Discretionary Denial. This means the PTAB exercised its discretion not to institute a trial, rather than making a decision on the merits of the patentability challenges.
• Judge panel: The judge panel for IPR2026-00016 consisted of Administrative Patent Judges Jessica K. Kaiser, Robert H. Hardie, and Brian P. Murphy.
• Petition grounds: The petition challenged claims 1-12 of US Patent No. 12,020,734, alleging obviousness under 35 U.S.C. § 103 over a combination of prior art references including U.S. Patent Publication No. 2007/0292720 (Suess), U.S. Patent No. 7,425,377 (Fullerton), and U.S. Patent No. 7,054,066 (Sato).
• Institution decision: Denied on 2026-03-07. The PTAB issued a discretionary denial under 35 U.S.C. § 314(a) and the factors set forth in Fintiv, citing the advanced stage of parallel district court litigation in Resonac Hard Disk Corp. et al. v. MR Technologies, GmbH, Civil Action No. 0:25-cv-01460 (D. Minn.). The Board noted that the district court trial was scheduled for June 2026, which was before the projected IPR final written decision date, weighing against institution.
• Final Written Decision: Not issued, as institution was denied.
• Settlement / termination: Not applicable, as institution was denied.
• Appeal: No appeal to the Federal Circuit, as institution was denied.
• Defensive value: While the petition challenged all claims (1-12), the discretionary denial means no claims were actually reviewed on their merits or invalidated by the PTAB. This means a defendant facing assertion of this patent will find that the patent's claims have not been weakened by PTAB challenges. However, the Fintiv-based denial implies that other potential petitioners not involved in the cited district court litigation, or those facing a different litigation posture, might still be able to successfully petition for IPR against this patent.

Strategic summary

All claims (1-12) of US patent 12020734 remain SUSTAINED and UNTESTED by a Final Written Decision at the PTAB. The sole IPR filed, IPR2026-00016, was denied institution on discretionary grounds, specifically due to the advanced stage of parallel district court litigation. This means the PTAB did not reach the merits of the patentability challenges, and thus no claims were canceled or confirmed patentable by the Board.

The estoppel landscape is favorable for any potential defendant not in privity with Resonac Hard Disk Corporation and not involved in the specific Minnesota district court litigation that triggered the discretionary denial. Since no Final Written Decision was issued, the statutory estoppel provisions of § 315(e)(2) do not apply. This leaves prior-art grounds, including those raised in IPR2026-00016 (e.g., Suess, Fullerton, Sato), theoretically available for a new IPR petition if the Fintiv factors (or any other discretionary factors) are not present. There is no pattern of multiple IPRs from the same petitioner or aggressive PTAB appeals by the patent owner yet, as only one proceeding has been filed and it was denied institution. The petitioner, Resonac Hard Disk Corporation, is an operating company rather than a defensive aggregator.

Recommended next steps

For a defendant facing assertion of US patent 12020734, it is important to note that all claims are currently sustained as no PTAB trial has concluded on the merits. The discretionary denial of IPR2026-00016 was based on the advanced stage of parallel district court litigation, not on the merits of the prior art. Therefore, the patent has not been "hardened" by a PTAB review.

If considering an IPR, a defendant would need to carefully assess whether their situation would avoid a similar discretionary denial, particularly concerning any parallel litigation. The institution decision for IPR2026-00016 can be reviewed at the USPTO PTAB Decisions portal to understand the Board's reasoning regarding the Fintiv factors: https://developer.uspto.gov/ptab-api/documents/IPR2026-00016/0/DD.
It is noteworthy that the patent has not faced a merits-based PTAB challenge, which can be a signal that it is either relatively strong or has not been widely asserted in contexts where IPRs are typically filed. Further analysis of the claims against potential prior art is warranted.

IPR2026-00016, Paper 11, Decision Denying Institution of Inter Partes Review (PTAB 2026-03-07). https://developer.uspto.gov/ptab-api/documents/IPR2026-00016/0/DD

Inventors

• Dieter Suess. The patent application lists "Individual" as the original assignee, indicating that Dieter Suess was likely the original applicant and inventor without an immediate corporate employer listed on the application. He later assigned the patent to Mr Technologies GmbH.

Original assignee

The patent was issued to the individual inventor, Dieter Suess. It was subsequently assigned to Mr Technologies GmbH on 2025-05-02. Mr Technologies GmbH is identified by Unified Patents as a Non-Practicing Entity (NPE). Its primary line of business appears to be intellectual property assertion, as it is involved in multiple litigation cases related to this patent family. There is no public information suggesting Mr Technologies GmbH ships products embodying the claims of the patent, which relate to multilayer exchange spring recording media. The company is currently active.

Assignment timeline

• 2025-05-02 (executed) / recorded 2025-05-02 — Reel 067097/0854
  • Conveyance: ASSIGNMENT
  • Assignor: SUESS, DIETER
  • Assignee: MR TECHNOLOGIES, GMBH
  • Correspondent: SCHNADER HARRISON SEGAL & LEWIS LLP, 1600 MARKET STREET SUITE 3600, PHILADELPHIA PA 19103-7286.
  • Context: Transfer-to-asserter from individual inventor to an IP holding company.

Timeline diagram

timeline
    title Ownership of US 12020734
    2021 : Application filed by individual
    2024 : Patent granted to individual
         : First litigation (8:24-cv-01848)
    2025 : Assigned to Mr Technologies GmbH
         : Other litigations filed
    2026 : IPR filed

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The patent was transferred from an individual inventor to MR TECHNOLOGIES, GMBH (Reel 067097/0854, 2025-05-02), which is identified by Unified Patents as a Non-Practicing Entity (NPE). There is no indication of Mr Technologies GmbH manufacturing or shipping products embodying the patent's claims.
2. Known asserter in the chain — Present. MR TECHNOLOGIES, GMBH is the current assignee (Reel 067097/0854, 2025-05-02) and is explicitly listed as an NPE by Unified Patents. Furthermore, the patent family is involved in multiple litigations and an IPR challenge.
3. Repeat correspondent across the chain — Not present. Only one assignment is recorded for this specific patent, so there is no recurrence of a correspondent within this chain.
4. Cascading transfers — Not present. Only a single assignment from the inventor to Mr Technologies GmbH is recorded.
5. Pre-litigation transfer — Not present. The first reported litigation case (8:24-cv-01848, filed in 2024) predates the assignment of the granted patent to MR TECHNOLOGIES, GMBH (Reel 067097/0854, 2025-05-02).
6. Bankruptcy fire-sale — Not present. There is no indication of bankruptcy filings related to the assignor or assignee in the chain.
7. Privateering — Unclear. While the patent is held by a known NPE, there is no public information or SEC filings directly linking Mr Technologies GmbH to an operating company's assertion strategy on their behalf.
8. Defensive aggregator (anti-NPE) — Not present. The patent is currently held by an entity actively involved in litigation, not a defensive aggregator.

Verdict

NPE — high confidence. The patent was assigned to Mr Technologies GmbH (Reel 067097/0854, 2025-05-02), an entity explicitly identified as a Non-Practicing Entity by Unified Patents. This transfer to a known asserter, coupled with ongoing litigation related to the patent family, provides strong evidence of an NPE assertion pattern.

For verification, see the USPTO Assignment Center search results for US12020734: https://assignmentcenter.uspto.gov/

Here is an analysis of the prior art citations for US patent 12020734, based on the provided patent text.

US12020734B2 - Multilayer exchange spring recording media

• Publication number: US12020734B2
• Publication date: 2024-06-25
• Filing date: 2021-10-04 (for US17/492,735, which this patent is granted from)
• Priority date: 2006-06-17

The invention describes a magnetic recording media comprising an exchange-coupled magnetic multilayer structure with a hard magnetic storage layer and a softer nucleation host. A key feature is that the nucleation host has an anisotropy varying in the film normal direction, assuming more than one value in substantial magnetic portions, allowing for separate adjustment of coercive field and thermal energy barrier.

Most Relevant Prior Art (Explicitly discussed in US12020734's "Description of Related Art"):

1. US6468670B1

   • Full Citation: US6468670B1 - Magnetic recording disk with composite perpendicular recording layer.
   • Publication/Filing Date: Priority date: 2000-01-19; Publication date: 2002-10-22.
   • Brief Description: This patent introduced a continuous ferromagnetic overlayer to increase the Signal to Noise Ratio (SNR) in magnetic recording media.
   • Potential Anticipated Claim(s) under 35 U.S.C. § 102: While US6468670B1 describes a composite perpendicular recording layer, its focus on a "continuous ferromagnetic overlayer" for SNR improvement is distinct from the specific exchange-spring mechanism and the spatially varying anisotropy in the nucleation host of US12020734. Therefore, broad claims in US12020734 relating to generic multilayer structures for recording media could potentially be considered, but the specific structural and functional features of claim 1 (e.g., nucleation host with increasing anisotropy, specific layer order, and separate adjustment of coercive field and thermal stability) are likely not directly anticipated.

2. US6280813B1

   • Full Citation: US6280813B1 - Magnetic recording media with antiferromagnetically coupled ferromagnetic films as the recording layer.
   • Publication/Filing Date: Priority date: 1999-10-08; Publication date: 2001-08-28.
   • Brief Description: This patent addressed thermal instability by replacing a conventional single magnetic recording layer with two ferromagnetic films that are antiferromagnetically coupled together across a nonferromagnetic spacer film.
   • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent's teaching of antiferromagnetically coupled ferromagnetic films addresses thermal instability, a problem also tackled by US12020734. Claims in US12020734 that broadly cover multilayer magnetic structures and coupling mechanisms (e.g., magnetic multilayer structure, exchange coupling, hard magnetic storage layer) could be related. However, US12020734's core invention focuses on a nucleation host with spatially varying anisotropy in the film normal direction and its specific function in controlling the coercive field while maintaining thermal stability, which is not explicitly taught by US6280813B1.

3. US6383668B1

   • Full Citation: US6383668B1 - Magnetic recording media with antiferromagnetically coupled host layer for the magnetic recording layer.
   • Publication/Filing Date: Priority date: 2000-03-27; Publication date: 2002-05-07.
   • Brief Description: This patent addressed thermal instability by utilizing a ferromagnetic layer coupled to a synthetic antiferromagnet.
   • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Similar to US6280813B1, this patent discusses antiferromagnetically coupled layers to improve thermal stability. While the general concept of using coupled layers to improve magnetic media properties might be seen as related, the specific inventive features of US12020734, particularly the multi-layered nucleation host with intentionally varied anisotropy (K1 < K2) and its placement relative to the hard magnetic storage layer, are not directly disclosed. Therefore, broad aspects of multilayer media might be implicated, but the specific claim elements of claim 1 would likely not be fully anticipated.

4. US5583727A

   • Full Citation: US5583727A - Multiple data layer magnetic recording data storage system with digital magnetoresistive read sensor.
   • Publication/Filing Date: Priority date: 1995-05-15; Publication date: 1996-12-10.
   • Brief Description: This patent proposed to overcome the thermal instability problem by employing thermally assisted recording.
   • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent addresses the problem of thermal instability in magnetic recording by proposing thermally assisted recording. While US12020734 also aims to overcome the "writeability problem" and achieve thermal stability, it does so through a specific magnetic multilayer structure (exchange spring media) rather than explicitly relying on thermal assistance during writing. Therefore, this patent would not directly anticipate the structural claims of US12020734, but rather represents a different approach to solving a common problem in the field.

Other Patent Citations from US12020734B2 (Alphabetical by Publication Number):

For these patents, without access to their full text, specific claim anticipation under 35 U.S.C. § 102 is difficult to determine with high confidence. The descriptions are based on the provided titles, and potential anticipation is generally related to their broad subject matter within magnetic recording media. The key distinguishing features of US12020734 are the nucleation host with anisotropy varying in the film normal direction and multiple ferromagnetic layers within the nucleation host with increasing anisotropy, as defined in claim 1.

• US3543249A

  • Full Citation: US3543249A - High permeability magnetic film structure.
  • Publication/Filing Date: Priority date: 1967-12-19; Publication date: 1970-11-24.
  • Brief Description: Concerns high permeability magnetic film structures.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent broadly relates to magnetic film structures. Any claims in US12020734 related to general magnetic film structures or underlayers could be considered broadly related, but the specific multilayer exchange spring structure and anisotropy gradient of US12020734's claims would likely not be anticipated.

• US5147732A

  • Full Citation: US5147732A - Longitudinal magnetic recording media and magnetic memory units.
  • Publication/Filing Date: Priority date: 1988-09-28; Publication date: 1992-09-15.
  • Brief Description: Concerns longitudinal magnetic recording media and magnetic memory units.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent pertains to longitudinal recording. US12020734 focuses on perpendicular recording media. While general concepts of magnetic recording media might overlap, the specific perpendicular anisotropy and layer configurations of US12020734, particularly claim 1, are unlikely to be anticipated.

• US5660930A

  • Full Citation: US5660930A - Multilayered thin films for perpendicular magnetic recording.
  • Publication/Filing Date: Priority date: 1994-04-04; Publication date: 1997-08-26.
  • Brief Description: Describes multilayered thin films specifically for perpendicular magnetic recording.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent directly relates to "multilayered thin films for perpendicular magnetic recording," which is the field of US12020734. Therefore, general claims in US12020734 (e.g., a hard magnetic storage layer formed from a perpendicular anisotropy material, or an exchange coupled magnetic multilayer structure) could be potentially anticipated if the specific features of US12020734's nucleation host with varying anisotropy are not present in this prior art.

• US5732049A

  • Full Citation: US5732049A - Magneto-optical recording medium of super-resolution type using in-plane magnetic layer, and information reproducing method using the same medium.
  • Publication/Filing Date: Priority date: 1994-12-27; Publication date: 1998-03-24.
  • Brief Description: Describes a magneto-optical recording medium of super-resolution type.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent concerns magneto-optical recording, which is a different technology from purely magnetic recording as claimed in US12020734. Direct anticipation of US12020734's claims is unlikely.

• US5756202A

  • Full Citation: US5756202A - Magnetic-optical recording medium.
  • Publication/Filing Date: Priority date: 1993-08-04; Publication date: 1998-05-26.
  • Brief Description: Describes a magnetic-optical recording medium.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Similar to US5732049A, this patent is for magneto-optical recording, making direct anticipation of US12020734's magnetic recording claims unlikely.

• US5851643A

  • Full Citation: US5851643A - Magnetic recording media and magnetic recording read-back system which uses such media.
  • Publication/Filing Date: Priority date: 1993-11-11; Publication date: 1998-12-22.
  • Brief Description: Concerns magnetic recording media and read-back systems.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent covers general magnetic recording media and systems. Broad elements of US12020734, such as a "magnetic recording system" or "magnetic recording medium," could be generally related, but the specific multilayer structure with varying anisotropy in the nucleation host, as detailed in claim 1, would need to be present for direct anticipation.

• JP2001118234A

  • Full Citation: JP2001118234A - Perpendicular magnetic recording medium and magnetic storage device.
  • Publication/Filing Date: Priority date: 1999-10-20; Publication date: 2001-04-27.
  • Brief Description: Describes a perpendicular magnetic recording medium and magnetic storage device.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent directly addresses perpendicular magnetic recording media. General aspects of US12020734, particularly those relating to perpendicular anisotropy materials and multilayer structures for such media, could be potentially anticipated. However, the specific features of the nucleation host with varied anisotropy (K1 < K2) are crucial for distinguishing US12020734.

• US20010051287A1

  • Full Citation: US20010051287A1 - Magnetic recording medium and magnetic recording apparatus.
  • Publication/Filing Date: Priority date: 2000-06-12; Publication date: 2001-12-13.
  • Brief Description: Describes a magnetic recording medium and apparatus.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent relates generally to magnetic recording media. Similar to JP2001118234A, broad aspects of US12020734 concerning magnetic recording media and their structures could be related, but the specific details of claim 1 of US12020734 would need to be thoroughly compared.

• JP2001344726A

  • Full Citation: JP2001344726A - Perpendicular magnetic recording medium and magnetic storage device.
  • Publication/Filing Date: Priority date: 2000-05-29; Publication date: 2001-12-14.
  • Brief Description: Describes a perpendicular magnetic recording medium and magnetic storage device.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is another in the field of perpendicular magnetic recording media. As with similar citations, general features of multilayer perpendicular media in US12020734 could be potentially anticipated, but the distinct nucleation host configuration of claim 1 would likely be a distinguishing factor.

• US20020094457A1

  • Full Citation: US20020094457A1 - Smoothing and stabilization of domain walls in perpendicularly polarized magnetic films.
  • Publication/Filing Date: Priority date: 2000-10-12; Publication date: 2002-07-18.
  • Brief Description: Focuses on smoothing and stabilizing domain walls in perpendicularly polarized magnetic films.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent's emphasis on domain wall behavior in perpendicular films is relevant to US12020734, which also relies on domain wall formation and propagation. Claims in US12020734 regarding domain wall formation in the nucleation host might be generally related, but the specific structure leading to the desired domain wall pinning and coercive field reduction in US12020734's claim 1 might be distinguishable.

• US20020146580A1

  • Full Citation: US20020146580A1 - Magnetic devices using nanocomposite materials.
  • Publication/Filing Date: Priority date: 2001-01-05; Publication date: 2002-10-10.
  • Brief Description: Concerns magnetic devices utilizing nanocomposite materials.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: US12020734 mentions "granular composite materials" and "granular structure" for the nucleation host. Therefore, general aspects of using nanocomposite or granular materials in magnetic recording media might be broadly related. However, the specific arrangement and anisotropy gradient of US12020734's layers, as defined in claim 1, would need a detailed comparison.

• US6535365B1

  • Full Citation: US6535365B1 - Magnetic tunneling structure having ferromagnetic layers of different crystallographic structure.
  • Publication/Filing Date: Priority date: 2000-02-17; Publication date: 2003-03-18.
  • Brief Description: Describes a magnetic tunneling structure with ferromagnetic layers of different crystallographic structure.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent appears to be related to magnetic tunneling junctions rather than magnetic recording media for data storage. While it involves ferromagnetic layers, the application and specific structure are likely distinct from US12020734's recording media claims.

• US20030099869A1

  • Full Citation: US20030099869A1 - Perpendicular magnetic recording medium and magnetic recording/reproducing apparatus using the same.
  • Publication/Filing Date: Priority date: 2001-11-27; Publication date: 2003-05-29.
  • Brief Description: Describes a perpendicular magnetic recording medium and apparatus.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: As with other perpendicular magnetic recording media patents, general aspects could be related. However, the specific features of US12020734's nucleation host and its function for controlling coercive field separately from thermal stability would need detailed review for direct anticipation.

• US20030108721A1

  • Full Citation: US20030108721A1 - Thermally - assisted magnetic recording disk with recording layer exchange- coupled to antiferromagnetic-to-ferromagnetic switching layer.
  • Publication/Filing Date: Priority date: 2001-12-11; Publication date: 2003-06-12.
  • Brief Description: Describes a thermally-assisted magnetic recording disk with a recording layer exchange-coupled to an antiferromagnetic-to-ferromagnetic switching layer.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent shares similarities with the Thiele et al. paper discussed in the background of US12020734. It involves exchange coupling and aims to lower the coercive field, similar to US12020734. However, it specifically teaches "thermally-assisted" recording and an "antiferromagnetic-to-ferromagnetic switching layer," which is a different mechanism from US12020734's reliance on spatially varying anisotropy in the nucleation host. Claims relating to exchange coupling and reduction of coercive field might be broadly implicated, but the specific means to achieve this differ.

• US20040009375A1

  • Full Citation: US20040009375A1 - Perpendicular magnetic recording media, manufacturing process of the same, and magnetic storage apparatus using the same.
  • Publication/Filing Date: Priority date: 2002-07-05; Publication date: 2004-01-15.
  • Brief Description: Describes perpendicular magnetic recording media and its manufacturing process.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent covers perpendicular recording media. General structural claims in US12020734 could be potentially related, but the specific nucleation host with varied anisotropy of claim 1 would need to be absent from this prior art for US12020734 to be novel.

• US20040053078A1

  • Full Citation: US20040053078A1 - Magnetic recording medium and magnetic recording/reproducing apparatus.
  • Publication/Filing Date: Priority date: 2002-06-28; Publication date: 2004-03-18.
  • Brief Description: Describes a magnetic recording medium and magnetic recording/reproducing apparatus.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Similar to other general magnetic recording media patents, broad claims of US12020734 might be related. The specific details of the multi-layered nucleation host with varied anisotropy in US12020734's claim 1 are the key for distinguishing.

• US20040057156A1

  • Full Citation: US20040057156A1 - Perpendicular magnetic recording media.
  • Publication/Filing Date: Priority date: 2002-09-19; Publication date: 2004-03-25.
  • Brief Description: Describes perpendicular magnetic recording media.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is directly in the field of perpendicular magnetic recording media. Claims in US12020734 relating to general perpendicular media configurations could be potentially anticipated. However, the unique features of US12020734's nucleation host with an anisotropy gradient (K1 < K2) are crucial for differentiation.

• US6730421B1

  • Full Citation: US6730421B1 - Magnetic recording medium and its production method, and magnetic recorder.
  • Publication/Filing Date: Priority date: 1999-05-11; Publication date: 2004-05-04.
  • Brief Description: Describes a magnetic recording medium, its production method, and a magnetic recorder.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: General aspects of magnetic recording media and systems could be related. The specific multilayer structure with varied anisotropy within the nucleation host of US12020734 is the primary distinguishing feature.

• US6777112B1

  • Full Citation: US6777112B1 - Stabilized recording media including coupled discontinuous and continuous magnetic layers.
  • Publication/Filing Date: Priority date: 2000-10-10; Publication date: 2004-08-17.
  • Brief Description: Describes stabilized recording media with coupled discontinuous and continuous magnetic layers.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent deals with "coupled discontinuous and continuous magnetic layers" for stabilization, which is broadly related to the multilayered and exchange-coupled nature of US12020734. Claims related to coupled magnetic layers could be considered. The specific definition of the nucleation host in claim 1, particularly its internal layers with varying anisotropy, would be key to differentiating US12020734.

• US20040191576A1

  • Full Citation: US20040191576A1 - Magnetic recording medium, method manufacture therefor, and apparatus for magnetic reproducing and reproducing recordings.
  • Publication/Filing Date: Priority date: 2001-02-28; Publication date: 2004-09-30.
  • Brief Description: Describes a magnetic recording medium, its manufacturing method, and apparatus for recording and reproducing.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: General claims concerning magnetic recording media and systems might be related. The specific multilayer structure of US12020734's nucleation host with its anisotropy gradient is the distinguishing feature.

• US6841259B1

  • Full Citation: US6841259B1 - Magnetic thin film, production method therefor, evaluation method therefor and magnetic head using it, magnetic recording device and magnetic device.
  • Publication/Filing Date: Priority date: 2000-05-31; Publication date: 2005-01-11.
  • Brief Description: Describes a magnetic thin film and related technologies.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent broadly covers magnetic thin films. General claims of US12020734 concerning magnetic layers could be related, but the specific exchange-spring multilayer structure and anisotropy variation within the nucleation host as detailed in claim 1 would need to be considered for direct anticipation.

• US6852426B1

  • Full Citation: US6852426B1 - Hybrid anti-ferromagnetically coupled and laminated magnetic media.
  • Publication/Filing Date: Priority date: 2001-12-20; Publication date: 2005-02-08.
  • Brief Description: Describes hybrid antiferromagnetically coupled and laminated magnetic media.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent also deals with coupled and laminated magnetic media, including antiferromagnetic coupling, similar to the general concepts addressed in the background of US12020734. Claims relating to multilayered and coupled magnetic media could be potentially anticipated. However, the specific design of US12020734's nucleation host with its spatially varying anisotropy and its particular function in the exchange-spring mechanism are likely distinguishing.

• US20050053803A1

  • Full Citation: US20050053803A1 - Magnetic recording medium, magnetic storage apparatus and recording method.
  • Publication/Filing Date: Priority date: 2003-09-05; Publication date: 2005-03-10.
  • Brief Description: Describes a magnetic recording medium, magnetic storage apparatus, and recording method.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: General claims of US12020734 concerning magnetic recording media and systems might be related. The specific multilayer structure with varied anisotropy within the nucleation host of US12020734 is the distinguishing feature.

• US20050058855A1

  • Full Citation: US20050058855A1 - Anti-ferromagnetically coupled perpendicular magnetic recording media with oxide.
  • Publication/Filing Date: Priority date: 2001-11-30; Publication date: 2005-03-17.
  • Brief Description: Describes antiferromagnetically coupled perpendicular magnetic recording media with oxide.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent also addresses perpendicular recording media with antiferromagnetic coupling and includes oxide. Claims in US12020734 regarding general perpendicular recording media and coupling mechanisms could be related. However, the explicit teaching of a nucleation host with internally varying anisotropy (K1 < K2) as described in claim 1 is likely a distinguishing factor.

• US6881497B2

  • Full Citation: US6881497B2 - ‘Thermal spring’ magnetic recording media for writing using magnetic and thermal gradients.
  • Publication/Filing Date: Priority date: 2001-06-04; Publication date: 2005-04-19.
  • Brief Description: Describes "thermal spring" magnetic recording media for writing using magnetic and thermal gradients.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent introduces "thermal spring" media, which conceptually relates to the "exchange spring" media of US12020734 in terms of using graded magnetic properties for writing. While the mechanism involves thermal gradients, the idea of a "spring" or graded magnetic property is somewhat analogous. Claims in US12020734 broadly related to managing magnetic properties for easier writing could be considered, but the specific structural elements of US12020734's nucleation host are likely distinct.

• US6893746B1

  • Full Citation: US6893746B1 - Magnetic recording medium with high thermal stability, method for producing the same, and magnetic recording apparatus.
  • Publication/Filing Date: Priority date: 1999-10-29; Publication date: 2005-05-17.
  • Brief Description: Describes a magnetic recording medium with high thermal stability.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent addresses high thermal stability, a primary goal of US12020734. General claims related to achieving thermal stability in recording media could be related. However, the specific structural solution of US12020734 (i.e., the multilayer nucleation host with varied anisotropy) is a key distinguishing feature.

• US20050181237A1

  • Full Citation: US20050181237A1 - Perpendicular magnetic recording medium.
  • Publication/Filing Date: Priority date: 2004-01-09; Publication date: 2005-08-18.
  • Brief Description: Describes a perpendicular magnetic recording medium.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This is another patent in the field of perpendicular magnetic recording media. General claims in US12020734 related to perpendicular media could be potentially anticipated. However, the specific multilayer structure and anisotropy gradient of the nucleation host in claim 1 remain a distinguishing characteristic.

• US20050244679A1

  • Full Citation: US20050244679A1 - Perpendicular magnetic recording medium, manufacturing process of the same, and magnetic recording/reproducing apparatus using the same.
  • Publication/Filing Date: Priority date: 2004-04-15; Publication date: 2005-11-03.
  • Brief Description: Describes a perpendicular magnetic recording medium and its manufacturing process.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Similar to other perpendicular recording media patents, general features might be related. The specific layering and anisotropy variation of US12020734's nucleation host are important for differentiation.

• US20060092696A1

  • Full Citation: US20060092696A1 - Storage element and memory.
  • Publication/Filing Date: Priority date: 2004-11-01; Publication date: 2006-05-04.
  • Brief Description: Describes a storage element and memory.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent covers a broad category of storage elements. General claims of US12020734 related to recording media as a storage element could be related, but the specific details of the magnetic multilayer structure are key.

• US7054066B2

  • Full Citation: US7054066B2 - Projection display device having micro-lenses.
  • Publication/Filing Date: Priority date: 2000-04-25; Publication date: 2006-05-30.
  • Brief Description: Describes a projection display device.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is completely unrelated to magnetic recording media. No direct anticipation of US12020734's claims is expected.

• US20060147758A1

  • Full Citation: US20060147758A1 - Perpendicular magnetic recording medium with magnetically resetable single domain soft magnetic underlayer.
  • Publication/Filing Date: Priority date: 2005-01-06; Publication date: 2006-07-06.
  • Brief Description: Describes a perpendicular magnetic recording medium with a magnetically resetable single domain soft magnetic underlayer.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent describes a perpendicular magnetic recording medium with a soft magnetic underlayer, which is also a component of US12020734. Claims relating to the underlayer or the general structure of perpendicular recording media could be broadly related. However, the novel nucleation host of US12020734 with its varied anisotropy and layering is the key distinguishing factor.

• US20060204792A1

  • Full Citation: US20060204792A1 - Magnetic recording medium, production process therefor, and magnetic recording and reproducing apparatus.
  • Publication/Filing Date: Priority date: 2004-04-06; Publication date: 2006-09-14.
  • Brief Description: Describes a magnetic recording medium, its production process, and related apparatus.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: General claims concerning magnetic recording media and systems might be broadly related. The specific multilayer structure with varied anisotropy within the nucleation host of US12020734 is the distinguishing feature.

• US20060210834A1

  • Full Citation: US20060210834A1 - Laminated magnetic thin films with sublayers for magnetic recording.
  • Publication/Filing Date: Priority date: 2005-03-18; Publication date: 2006-09-21.
  • Brief Description: Describes laminated magnetic thin films with sublayers for magnetic recording.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is highly relevant as it describes "laminated magnetic thin films with sublayers for magnetic recording," which directly relates to the multilayer structure of US12020734. Claims in US12020734 relating to the general concept of multiple magnetic layers and sublayers could be potentially anticipated. The specific definition of the nucleation host in claim 1, particularly its internal layers with increasing anisotropy (K1 < K2) and their exchange coupling, would need to be thoroughly compared to this prior art for novelty.

• US20070072011A1

  • Full Citation: US20070072011A1 - Perpendicular magnetic recording media with magnetic anisotropy/coercivity gradient and local exchange coupling.
  • Publication/Filing Date: Priority date: 2005-09-27; Publication date: 2007-03-29.
  • Brief Description: Describes perpendicular magnetic recording media with a magnetic anisotropy/coercivity gradient and local exchange coupling.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is highly relevant as it explicitly teaches "magnetic anisotropy/coercivity gradient and local exchange coupling" in perpendicular media, which aligns closely with the core invention of US12020734. Claim 1 of US12020734, particularly the "anisotropy varying in the film normal direction" within the nucleation host and the strong exchange coupling, could be directly anticipated depending on the specific implementation of the gradient and coupling in US20070072011A1. This patent would require careful examination against US12020734's claims.

• US20070140951A1

  • Full Citation: US20070140951A1 - Nano-sized particles, processes of making, compositions and uses thereof.
  • Publication/Filing Date: Priority date: 2003-12-11; Publication date: 2007-06-21.
  • Brief Description: Concerns nano-sized particles and their uses.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: US12020734 mentions "grains" and "grain diameter" for the nucleation host and hard magnetic storage layer. While this patent broadly covers nanoparticles, its relevance to the specific multilayer structure and magnetic properties of US12020734's recording media claims might be indirect, unless it specifically discusses such particles in the context of anisotropy gradients in recording media.

• US20070148499A1

  • Full Citation: US20070148499A1 - Perpendicular magnetic recording disk and manufacturing method thereof.
  • Publication/Filing Date: Priority date: 2004-06-30; Publication date: 2007-06-28.
  • Brief Description: Describes a perpendicular magnetic recording disk and its manufacturing method.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Another patent in the field of perpendicular recording media. General claims of US12020734 might be related. The specific multilayer structure and anisotropy gradient of the nucleation host in claim 1 are key for differentiation.

• US7238385B2

  • Full Citation: US7238385B2 - Antiferromagnetically coupled (AFC) media with flash CR interlayer between top magnetic layer and S2 magnetic layer.
  • Publication/Filing Date: Priority date: 2002-01-16; Publication date: 2007-07-03.
  • Brief Description: Describes antiferromagnetically coupled media with a flash CR interlayer.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent concerns antiferromagnetically coupled media with specific interlayers. While US12020734 mentions that coupling "may be ferromagnetic or antiferromagnetic", the primary invention is the graded anisotropy in the nucleation host. Claims related to general coupled multilayer media might be implicated, but the specific details of claim 1, particularly the increasing anisotropy within the nucleation host, are likely distinguishing.

• US20070188923A1

  • Full Citation: US20070188923A1 - Vertical magnetic recording medium.
  • Publication/Filing Date: Priority date: 2006-02-15; Publication date: 2007-08-16.
  • Brief Description: Describes a vertical magnetic recording medium (synonymous with perpendicular recording).
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent directly relates to perpendicular (vertical) magnetic recording media. General claims of US12020734, such as an exchange coupled magnetic multilayer structure including a hard magnetic storage layer, could be potentially anticipated. The specific details of the nucleation host's internal structure and anisotropy gradient in claim 1 are critical for novelty.

• US20070224453A1

  • Full Citation: US20070224453A1 - Magnetic recording medium and magnetic recording apparatus.
  • Publication/Filing Date: Priority date: 2006-03-27; Publication date: 2007-09-27.
  • Brief Description: Describes a magnetic recording medium and apparatus.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: General claims related to magnetic recording media could be broadly related. The specific multilayer structure with varied anisotropy within the nucleation host of US12020734 is the distinguishing feature.

• US20070243418A1

  • Full Citation: US20070243418A1 - Perpendicular magnetic recording medium with laminated recording layers formed of exchange-coupled ferromagnetic layers.
  • Publication/Filing Date: Priority date: 2006-04-12; Publication date: 2007-10-18.
  • Brief Description: Describes a perpendicular magnetic recording medium with laminated recording layers formed of exchange-coupled ferromagnetic layers.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is highly relevant, explicitly teaching "laminated recording layers formed of exchange-coupled ferromagnetic layers" in perpendicular media, which strongly overlaps with US12020734's claims. Claims in US12020734 regarding the general exchange-coupled multilayer structure and the presence of a hard magnetic storage layer could be anticipated. The key for US12020734's novelty lies in the specific details of the anisotropy gradient within the nucleation host as claimed in claim 1.

• US20070292720A1

  • Full Citation: US20070292720A1 - Multilayer Exchange Spring Recording Media.
  • Publication/Filing Date: Priority date: 2006-06-17; Publication date: 2007-12-20.
  • Brief Description: This is an earlier publication of an application by the same inventor (Dieter Suess) with the same title as US12020734B2, and the same priority date. This is likely a parent or related application in the patent family.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Given that this is an earlier publication from the same priority date and by the same inventor, it likely represents the same or very similar invention. If the claims in US20070292720A1 are substantially similar to those in US12020734B2, then US20070292720A1 would fully anticipate US12020734B2 under 35 U.S.C. § 102(a)(2) (prior art publication of the applicant's own invention). However, as a family member, this is generally considered "applicant's own prior art" and may not pose an novelty bar if common inventorship or assignment exists and appropriate terminal disclaimers or priority claims are made. It serves to establish the earliest public disclosure of the invention.

• US20080032490A1

  • Full Citation: US20080032490A1 - Nanocylinder arrays.
  • Publication/Filing Date: Priority date: 2000-03-22; Publication date: 2008-02-07.
  • Brief Description: Concerns nanocylinder arrays.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: While US12020734 mentions granular structures, the focus on "nanocylinder arrays" is a specific geometry. Unless these nanocylinder arrays are taught in the context of a multilayer exchange spring media with varying anisotropy as in claim 1 of US12020734, direct anticipation is unlikely.

• US7384699B2

  • Full Citation: US7384699B2 - Magnetic recording media with tuned exchange coupling and method for fabricating same.
  • Publication/Filing Date: Priority date: 2004-08-02; Publication date: 2008-06-10.
  • Brief Description: Describes magnetic recording media with tuned exchange coupling.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent's focus on "tuned exchange coupling" is very relevant to US12020734, which emphasizes strong exchange coupling. Claims in US12020734 involving exchange coupling between layers could be potentially anticipated. The distinct feature of US12020734 is the varying anisotropy within the nucleation host, and the method of achieving tuned exchange coupling in this patent would need to be compared against US12020734's claim 1.

• US7425377B2

  • Full Citation: US7425377B2 - Incoherently-reversing magnetic laminate with exchange coupled ferromagnetic layers.
  • Publication/Filing Date: Priority date: 2005-02-04; Publication date: 2008-09-16.
  • Brief Description: Describes an incoherently-reversing magnetic laminate with exchange-coupled ferromagnetic layers.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is highly relevant as it describes "exchange coupled ferromagnetic layers" in a "magnetic laminate" with "incoherently-reversing" magnetization, which relates to the domain wall formation and propagation in US12020734. Claims in US12020734 relating to exchange-coupled multilayer structures could be potentially anticipated. The specific anisotropy gradient in the nucleation host of US12020734's claim 1 would be crucial for establishing novelty.

• US20090009914A1

  • Full Citation: US20090009914A1 - Semiconductor Device Using Locating and Sign of the Spin of Electrons.
  • Publication/Filing Date: Priority date: 2004-05-07; Publication date: 2009-01-08.
  • Brief Description: Concerns a semiconductor device.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent appears unrelated to magnetic recording media. No direct anticipation of US12020734's claims is expected.

• US7550210B2

  • Full Citation: US7550210B2 - Perpendicular magnetic recording medium with multiple exchange-coupled magnetic layers having substantially similar anisotropy fields.
  • Publication/Filing Date: Priority date: 2006-03-09; Publication date: 2009-06-23.
  • Brief Description: Describes a perpendicular magnetic recording medium with multiple exchange-coupled magnetic layers having substantially similar anisotropy fields.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is highly relevant. It describes "multiple exchange-coupled magnetic layers" for perpendicular recording. Critically, it states "substantially similar anisotropy fields," which directly contrasts with US12020734's core invention of a nucleation host with varying anisotropy (K1 < K2) from layer to layer (Claim 1). Therefore, while general aspects of multilayer perpendicular media might be related, this patent's explicit teaching of similar anisotropy fields highlights the novelty of US12020734's graded anisotropy.

• US7572526B2

  • Full Citation: US7572526B2 - Perpendicular magnetic recording medium with exchange-spring structure having multiple exchange-spring layers and recording system for the medium.
  • Publication/Filing Date: Priority date: 2007-02-18; Publication date: 2009-08-11.
  • Brief Description: Describes a perpendicular magnetic recording medium with an exchange-spring structure having multiple exchange-spring layers.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is extremely relevant as it uses the term "exchange-spring structure having multiple exchange-spring layers" for perpendicular recording. US12020734 is also titled "Multilayer exchange spring recording media." Given the overlap in terminology and subject matter, claims in US12020734 relating to exchange-spring structures and multiple layers, including claim 1, could be directly anticipated if the specific "anisotropy varying in the film normal direction" and "increasing anisotropy K2 greater than K1" within the nucleation host are also present in US7572526B2. This would require a detailed comparison.

• US7687157B2

  • Full Citation: US7687157B2 - Perpendicular recording media having an exchange-spring structure.
  • Publication/Filing Date: Priority date: 2005-02-04; Publication date: 2010-03-30.
  • Brief Description: Describes perpendicular recording media having an exchange-spring structure.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is also highly relevant due to its explicit mention of "exchange-spring structure" in perpendicular recording media. Similar to US7572526B2, claims in US12020734 regarding exchange-spring structures and multilayer recording media could be directly anticipated if the specific graded anisotropy in the nucleation host, as detailed in claim 1, is present in this prior art.

• US7833640B2

  • Full Citation: US7833640B2 - Intermediate tri-layer structure for perpendicular recording media.
  • Publication/Filing Date: Priority date: 2005-08-19; Publication date: 2010-11-16.
  • Brief Description: Describes an intermediate tri-layer structure for perpendicular recording media.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: US12020734 mentions a "trilayer structure" in its background. This patent, with its "tri-layer structure for perpendicular recording media," is highly relevant. Claims in US12020734 relating to multilayer structures, especially those describing a nucleation host with multiple layers (e.g., first and second ferromagnetic layers as in claim 1), could be potentially anticipated. The specific anisotropy gradient (K1 < K2) and its function in the nucleation host would need to be compared for novelty.

• US8557409B2

  • Full Citation: US8557409B2 - Perpendicular magnetic recording medium.
  • Publication/Filing Date: Priority date: 2010-08-02; Publication date: 2013-10-15.
  • Brief Description: Describes a perpendicular magnetic recording medium.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This is a later patent (after US12020734's priority date). It would not be prior art under § 102 (a) or (b) unless it claims an earlier priority date (which it does not, its priority date is 2010-08-02, which is after US12020734's 2006-06-17 priority date). However, it is cited. It could potentially anticipate under 35 U.S.C. § 102(e) if it was filed earlier and published later than the priority date of US12020734. Given its priority date (2010), it would not be anticipatory prior art for US12020734 (priority 2006).

• US9966095B2

  • Full Citation: US9966095B2 - Perpendicular magnetic recording media having an extremely low Hk layer.
  • Publication/Filing Date: Priority date: 2016-08-02; Publication date: 2018-05-08.
  • Brief Description: Describes perpendicular magnetic recording media having an extremely low Hk (anisotropy field) layer.
  • Potential Anticipated Claim(s) under 35 U.S.C. § 102: This patent is a later patent (priority 2016) and thus not prior art for US12020734 (priority 2006).

The following patents are also listed under "Patent Citations (65)" but their data (priority/publication dates) is not fully provided in the specific format, or they appear to be family members of US12020734 itself:

• US7989096B2: This patent has a priority date of 2005-02-04 and publication date 2011-08-02. Title: "Perpendicular recording media having an exchange-spring structure". This is very similar to US7687157B2. It would be highly relevant and needs careful comparison, especially concerning the graded anisotropy in the nucleation host.
• US7846564B2: This patent has a priority date of 2005-09-27 and publication date 2010-12-07. Title: "Perpendicular magnetic recording media with magnetic anisotropy/coercivity gradient and local exchange coupling". This patent is very similar to US20070072011A1, by the same assignee, and thus highly relevant as it explicitly teaches anisotropy/coercivity gradients.
• US20110076516A1: This patent has a priority date of 2005-09-27 and publication date 2011-03-31. Title: "Perpendicular Magnetic Recording Media with Magnetic Anisotropy Gradient and Local Exchange Coupling". This is another publication of the same subject matter by the same assignee as US7846564B2 and US20070072011A1.
• US7488545B2: This patent has a priority date of 2006-04-12 and publication date 2009-02-10. Title: "Perpendicular magnetic recording medium with laminated recording layers formed of exchange-coupled ferromagnetic layers". This is another patent by the same assignee as US20070243418A1 and with the same priority date.
• US9928864B2: This patent has a priority date of 2006-06-17 and publication date 2018-03-27. Title: "Multilayer exchange spring recording media". This is another patent by Dieter Suess, with the same priority date as US12020734, and the same title. This is a family member.
• US9978413B2: This patent has a priority date of 2006-06-17 and publication date 2018-05-22. Title: "Multilayer exchange spring recording media". This is another patent by Dieter Suess, with the same priority date as US12020734, and the same title. This is a family member.
• US20180211689A1: This patent has a priority date of 2006-06-17 and publication date 2018-07-26. Title: "Multilayer exchange spring recording media". This is another patent by Dieter Suess, with the same priority date as US12020734, and the same title. This is a family member.
• US20180268852A1: This patent has a priority date of 2006-06-17 and publication date 2018-09-20. Title: "Multilayer exchange spring recording media". This is another patent by Dieter Suess, with the same priority date as US12020734, and the same title. This is a family member.
• US11133031B2: This patent has a priority date of 2006-06-17 and publication date 2021-09-28. Title: "Multilayer exchange spring recording media". This is another patent by Dieter Suess, with the same priority date as US12020734, and the same title. This is a family member.
• US11138997B2: This patent has a priority date of 2006-06-17 and publication date 2021-10-05. Title: "Multilayer exchange spring recording media". This is another patent by Dieter Suess, with the same priority date as US12020734, and the same title. This is a family member.

In summary, the most relevant prior art (excluding family members of US12020734) would be those that explicitly discuss perpendicular magnetic recording media with multilayer structures, exchange coupling, and particularly those addressing anisotropy or coercivity gradients. These would include US5660930A, US20060210834A1, US20070072011A1, US7384699B2, US7425377B2, US7550210B2, US7572526B2, US7687157B2, US7833640B2, and the various family members citing the same priority date. For these, a detailed claim-by-claim comparison would be necessary to determine actual anticipation under 35 U.S.C. § 102.

Obviousness Analysis under 35 U.S.C. § 103

A patent claim is obvious if "the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains." (35 U.S.C. § 103). The motivation to combine prior art references can come from the knowledge of those skilled in the art, from the prior art reference itself, or from the nature of the problem to be solved. It's important to note that merely identifying all elements of an invention in the prior art is not enough; there must be a clear reason or rationale for a person of ordinary skill in the art (PHOSITA) to combine those elements in the claimed manner. The combination need not be "the best option, only a suitable option."

The independent claim, Claim 1, describes a magnetic recording system. It includes a writing head and a disk with a magnetic recording medium, which comprises an essentially non-magnetic substrate, an underlayer, and an exchange-coupled magnetic multilayer structure. This structure further includes a hard magnetic storage layer and a nucleation host. The hard magnetic storage layer is a perpendicular anisotropy material with a coercive field Hc > 0.5 T. The nucleation host has a coercive field Hn < Hs and is formed on the hard magnetic storage layer. The nucleation host itself contains at least a first ferromagnetic layer with anisotropy K1 and a second ferromagnetic layer between the first layer and the hard magnetic storage layer with an increased anisotropy K2 (K2 > K1), with an exchange coupling layer between the first and second ferromagnetic layers.

Combination 1: Suess et al. (US20070292720A1 or equivalent) in view of Victora and Shen (2005)

Prior Art References:

• Suess et al. (US20070292720A1): This patent application (which is an earlier publication of the same family as US12020734B2) describes a multilayer exchange spring recording media consisting of a magnetically hard magnetic storage layer strongly exchange coupled to a softer nucleation host. The nucleation host can consist of one or more ferromagnetic coupled layers, and for a multilayer nucleation host, the anisotropy increases from layer to layer. The patent also mentions that the nucleation host decreases the coercive field significantly while keeping the energy barrier of the hard layer almost unchanged, addressing the writeability problem. Suess et al. explicitly discusses "exchange spring media" where the recording media consists of exchange-coupled soft and hard magnetic layers, allowing good writeability due to the soft layer while maintaining thermal stability of the hard layer.
• Victora and Shen (2005): In their paper "Composite Media for Perpendicular Magnetic Recording," Victora and Shen proposed magnetic multilayer structures composed of magnetically hard and magnetically soft layers. Their model, however, assumed the magnetization of the soft and hard parts of each grain remained uniform, and to decrease the coercive field, the exchange coupling between these layers had to be reduced with a decoupling layer.

Motivation to Combine:

A person having ordinary skill in the art (PHOSITA) in the field of magnetic recording media would have been motivated to combine the teachings of Suess et al. and Victora and Shen to improve the writeability and thermal stability of high-density magnetic recording media.

Suess et al. explicitly addresses the writeability problem in perpendicular recording media by using a multilayer exchange spring recording media where a hard magnetic storage layer is strongly exchange coupled to a softer nucleation host. The core idea is that the anisotropy increases from layer to layer within the nucleation host.

While Victora and Shen also proposed magnetic multilayer structures with hard and soft layers to address recording density challenges, their approach focused on reducing exchange coupling for coercive field decrease and assumed uniform magnetization within layers. Suess et al., however, differentiates itself by stating that "this was in contrast to the paper 'Exchange spring media for perpendicular recording,' . . . where states with inhomogeneous magnetization were formed." This suggests Suess et al. was aware of Victora and Shen's work and proposed an alternative that did not rely on reducing the exchange coupling to decrease coercive field.

However, Claim 1 of US12020734 specifies that the first and second ferromagnetic layers within the nucleation host are exchange coupled with an exchange coupling layer. While Suess et al. (the prior art publication) mentions that the overall exchange coupling between the nucleation host and the hard magnetic storage layer can be "direct or via a thin coupling layer," it doesn't explicitly detail an internal exchange coupling layer between the ferromagnetic layers within the nucleation host.

Therefore, a PHOSITA, recognizing the benefits of the graded anisotropy in the nucleation host taught by Suess et al. for addressing the writeability problem, and being familiar with the general concept of using coupling layers in multilayer magnetic structures (as discussed by Victora and Shen for decoupling, or by Suess et al. itself for coupling the nucleation host to the hard layer), would have found it obvious to introduce an exchange coupling layer between the internal layers of the nucleation host to ensure strong exchange coupling and thus facilitate the domain wall propagation critical to the "exchange spring" mechanism. The goal would be to optimize the benefits of the gradually increasing anisotropy in the nucleation host, as shown by Suess et al. to reduce the coercive field and maintain thermal stability. This would be a predictable alteration to achieve a known result in the field of multilayer magnetic recording media.

Patent Term Adjustments (PTA)

Patent Term Adjustment (PTA) is granted to compensate for delays caused by the USPTO during the prosecution of a patent application. The USPTO automatically determines the period of PTA and provides a notice of this determination by the patent's issue date.

Without access to the official USPTO patent record for US12020734 (e.g., Patent Center or PAIR), the exact PTA granted cannot be definitively stated. However, the patent text indicates a filing date of October 4, 2021, and a publication (grant) date of June 25, 2024. This period of approximately 2 years and 8 months (32 months) from filing to grant is less than the 36-month timeframe specified for certain USPTO delays, which could suggest minimal or no PTA in this category. Nonetheless, other types of delays (e.g., issuance of a first office action within 14 months, responses to replies within 4 months, or patent issuance within 4 months after issue fee payment) can also contribute to PTA.

Patent Term Extensions (PTE)

Patent Term Extensions (PTE) are distinct from PTA and are primarily available for patents claiming products that require pre-market regulatory review, such as pharmaceuticals, medical devices, food additives, and color additives. The purpose of PTE is to compensate patentees for the time lost during this regulatory review process.

The subject matter of US12020734, "Multilayer exchange spring recording media," does not fall within the categories of products requiring pre-market regulatory approval (e.g., FDA approval). Therefore, it is highly unlikely that US12020734 would be eligible for any Patent Term Extension.

Continuation Applications

A continuation application is a new patent application that pursues additional claims to an invention already disclosed in an earlier-filed, co-pending "parent" application. The continuation must share the same disclosure as the parent application, without adding new subject matter, and have at least one common inventor. It must be filed before the patenting, abandonment, or termination of proceedings on the parent application.

The provided patent text and family information show the following related family members, which could be continuation applications:

• US17/492,735: This is the application number for US12020734.
• US11/424,859: (US9978413B2) Filed 2006-06-17.
• US12/619,849: (US9928864B2) Filed 2009-11-17.
• US15/925,749: (US11138997B2) Filed 2018-03-19.
• US15/985,661: (US11133031B2) Filed 2018-05-21.
• US17/486,608: (US11908500B2) Filed 2021-09-27.
• US18/503,873: (US20240079030A1) Filed 2023-11-07.

All these applications claim priority from the earliest priority date of 2006-06-17, indicating they are likely continuation or divisional applications stemming from an original application filed on that date. Specifically, US17/492,735 (which resulted in US12020734) claims priority to US17/492,735, which itself has a priority date of 2006-06-17, confirming its lineage within this family.

Divisional Applications

A divisional application arises when the USPTO determines that a single application claims two or more independent and distinct inventions and requires the applicant to restrict the application to one invention. The applicant can then file a divisional application for the non-elected invention(s), which benefits from the filing date of the original application.

As with continuation applications, the numerous family members of US12020734, all sharing the same priority date of 2006-06-17, suggest that divisional applications may exist within this patent family. Without direct access to the prosecution history of each application, it is not possible to definitively identify which specific applications are divisional rather than continuation applications.

Related Family Members

The patent text explicitly lists several related family members, all sharing the priority date of 2006-06-17 and having the title "Multilayer exchange spring recording media":

• US11/424,859 (US9978413B2)
• US12/619,849 (US9928864B2)
• US15/925,749 (US11138997B2)
• US15/985,661 (US11133031B2)
• US17/486,608 (US11908500B2)
• US17/492,735 (US12020734B2 - the patent in question)
• US18/503,873 (US20240079030A1)

These are all applications claiming priority to the same earliest date, forming a single patent family.

Projected Expiration Date

For applications filed on or after June 8, 1995, the term of a patent generally ends 20 years from the date on which the application for the patent was filed in the United States, or, if it claims priority to an earlier application, 20 years from the filing date of the earliest such application.

US12020734 was filed on October 4, 2021 (Application number US17/492,735), but its priority date is June 17, 2006. Therefore, the expiration date is calculated from the earliest priority date.

Expiration Date = Earliest Priority Date + 20 years
Expiration Date = 2006-06-17 + 20 years = 2026-06-17.

This calculation does not account for any Patent Term Adjustment (PTA) that may have been granted. As previously noted, without access to the official USPTO record for US12020734, the exact PTA is unknown. However, the Google Patents information indicates an "Anticipated expiration" date of 2026-06-17, which aligns with the 20-year term from the priority date, suggesting no significant PTA or that any PTA has already been factored into this anticipated date.